fs/exfat/namei.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
   4  */
   5
   6 #include <linux/iversion.h>
   7 #include <linux/namei.h>
   8 #include <linux/slab.h>
   9 #include <linux/buffer_head.h>
  10 #include <linux/nls.h>
  11
  12 #include "exfat_raw.h"
  13 #include "exfat_fs.h"
  14
  15 static inline unsigned long exfat_d_version(struct dentry *dentry)
  16 {
  17         return (unsigned long) dentry->d_fsdata;
  18 }
  19
  20 static inline void exfat_d_version_set(struct dentry *dentry,
  21                 unsigned long version)
  22 {
  23         dentry->d_fsdata = (void *) version;
  24 }
  25
  26 /*
  27  * If new entry was created in the parent, it could create the 8.3 alias (the
  28  * shortname of logname).  So, the parent may have the negative-dentry which
  29  * matches the created 8.3 alias.
  30  *
  31  * If it happened, the negative dentry isn't actually negative anymore.  So,
  32  * drop it.
  33  */
  34 static int exfat_d_revalidate(struct dentry *dentry, unsigned int flags)
  35 {
  36         int ret;
  37
  38         if (flags & LOOKUP_RCU)
  39                 return -ECHILD;
  40
  41         /*
  42          * This is not negative dentry. Always valid.
  43          *
  44          * Note, rename() to existing directory entry will have ->d_inode, and
  45          * will use existing name which isn't specified name by user.
  46          *
  47          * We may be able to drop this positive dentry here. But dropping
  48          * positive dentry isn't good idea. So it's unsupported like
  49          * rename("filename", "FILENAME") for now.
  50          */
  51         if (d_really_is_positive(dentry))
  52                 return 1;
  53
  54         /*
  55          * Drop the negative dentry, in order to make sure to use the case
  56          * sensitive name which is specified by user if this is for creation.
  57          */
  58         if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
  59                 return 0;
  60
  61         spin_lock(&dentry->d_lock);
  62         ret = inode_eq_iversion(d_inode(dentry->d_parent),
  63                         exfat_d_version(dentry));
  64         spin_unlock(&dentry->d_lock);
  65         return ret;
  66 }
  67
  68 /* returns the length of a struct qstr, ignoring trailing dots */
  69 static unsigned int exfat_striptail_len(unsigned int len, const char *name)
  70 {
  71         while (len && name[len - 1] == '.')
  72                 len--;
  73         return len;
  74 }
  75
  76 /*
  77  * Compute the hash for the exfat name corresponding to the dentry.  If the name
  78  * is invalid, we leave the hash code unchanged so that the existing dentry can
  79  * be used. The exfat fs routines will return ENOENT or EINVAL as appropriate.
  80  */
  81 static int exfat_d_hash(const struct dentry *dentry, struct qstr *qstr)
  82 {
  83         struct super_block *sb = dentry->d_sb;
  84         struct nls_table *t = EXFAT_SB(sb)->nls_io;
  85         const unsigned char *name = qstr->name;
  86         unsigned int len = exfat_striptail_len(qstr->len, qstr->name);
  87         unsigned long hash = init_name_hash(dentry);
  88         int i, charlen;
  89         wchar_t c;
  90
  91         for (i = 0; i < len; i += charlen) {
  92                 charlen = t->char2uni(&name[i], len - i, &c);
  93                 if (charlen < 0)
  94                         return charlen;
  95                 hash = partial_name_hash(exfat_toupper(sb, c), hash);
  96         }
  97
  98         qstr->hash = end_name_hash(hash);
  99         return 0;
 100 }
 101
 102 static int exfat_d_cmp(const struct dentry *dentry, unsigned int len,
 103                 const char *str, const struct qstr *name)
 104 {
 105         struct super_block *sb = dentry->d_sb;
 106         struct nls_table *t = EXFAT_SB(sb)->nls_io;
 107         unsigned int alen = exfat_striptail_len(name->len, name->name);
 108         unsigned int blen = exfat_striptail_len(len, str);
 109         wchar_t c1, c2;
 110         int charlen, i;
 111
 112         if (alen != blen)
 113                 return 1;
 114
 115         for (i = 0; i < len; i += charlen) {
 116                 charlen = t->char2uni(&name->name[i], alen - i, &c1);
 117                 if (charlen < 0)
 118                         return 1;
 119                 if (charlen != t->char2uni(&str[i], blen - i, &c2))
 120                         return 1;
 121
 122                 if (exfat_toupper(sb, c1) != exfat_toupper(sb, c2))
 123                         return 1;
 124         }
 125
 126         return 0;
 127 }
 128
 129 const struct dentry_operations exfat_dentry_ops = {
 130         .d_revalidate   = exfat_d_revalidate,
 131         .d_hash         = exfat_d_hash,
 132         .d_compare      = exfat_d_cmp,
 133 };
 134
 135 static int exfat_utf8_d_hash(const struct dentry *dentry, struct qstr *qstr)
 136 {
 137         struct super_block *sb = dentry->d_sb;
 138         const unsigned char *name = qstr->name;
 139         unsigned int len = exfat_striptail_len(qstr->len, qstr->name);
 140         unsigned long hash = init_name_hash(dentry);
 141         int i, charlen;
 142         unicode_t u;
 143
 144         for (i = 0; i < len; i += charlen) {
 145                 charlen = utf8_to_utf32(&name[i], len - i, &u);
 146                 if (charlen < 0)
 147                         return charlen;
 148
 149                 /*
 150                  * Convert to UTF-16: code points above U+FFFF are encoded as
 151                  * surrogate pairs.
 152                  * exfat_toupper() works only for code points up to the U+FFFF.
 153                  */
 154                 if (u > 0xFFFF) {
 155                         hash = partial_name_hash(exfat_high_surrogate(u), hash);
 156                         hash = partial_name_hash(exfat_low_surrogate(u), hash);
 157                 } else {
 158                         hash = partial_name_hash(exfat_toupper(sb, u), hash);
 159                 }
 160         }
 161
 162         qstr->hash = end_name_hash(hash);
 163         return 0;
 164 }
 165
 166 static int exfat_utf8_d_cmp(const struct dentry *dentry, unsigned int len,
 167                 const char *str, const struct qstr *name)
 168 {
 169         struct super_block *sb = dentry->d_sb;
 170         unsigned int alen = exfat_striptail_len(name->len, name->name);
 171         unsigned int blen = exfat_striptail_len(len, str);
 172         unicode_t u_a, u_b;
 173         int charlen, i;
 174
 175         if (alen != blen)
 176                 return 1;
 177
 178         for (i = 0; i < alen; i += charlen) {
 179                 charlen = utf8_to_utf32(&name->name[i], alen - i, &u_a);
 180                 if (charlen < 0)
 181                         return 1;
 182                 if (charlen != utf8_to_utf32(&str[i], blen - i, &u_b))
 183                         return 1;
 184
 185                 if (u_a <= 0xFFFF && u_b <= 0xFFFF) {
 186                         if (exfat_toupper(sb, u_a) != exfat_toupper(sb, u_b))
 187                                 return 1;
 188                 } else if (u_a > 0xFFFF && u_b > 0xFFFF) {
 189                         if (exfat_low_surrogate(u_a) !=
 190                                         exfat_low_surrogate(u_b) ||
 191                             exfat_high_surrogate(u_a) !=
 192                                         exfat_high_surrogate(u_b))
 193                                 return 1;
 194                 } else {
 195                         return 1;
 196                 }
 197         }
 198
 199         return 0;
 200 }
 201
 202 const struct dentry_operations exfat_utf8_dentry_ops = {
 203         .d_revalidate   = exfat_d_revalidate,
 204         .d_hash         = exfat_utf8_d_hash,
 205         .d_compare      = exfat_utf8_d_cmp,
 206 };
 207
 208 /* used only in search empty_slot() */
 209 #define CNT_UNUSED_NOHIT        (-1)
 210 #define CNT_UNUSED_HIT          (-2)
 211 /* search EMPTY CONTINUOUS "num_entries" entries */
 212 static int exfat_search_empty_slot(struct super_block *sb,
 213                 struct exfat_hint_femp *hint_femp, struct exfat_chain *p_dir,
 214                 int num_entries)
 215 {
 216         int i, dentry, num_empty = 0;
 217         int dentries_per_clu;
 218         unsigned int type;
 219         struct exfat_chain clu;
 220         struct exfat_dentry *ep;
 221         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 222         struct buffer_head *bh;
 223
 224         dentries_per_clu = sbi->dentries_per_clu;
 225
 226         if (hint_femp->eidx != EXFAT_HINT_NONE) {
 227                 dentry = hint_femp->eidx;
 228                 if (num_entries <= hint_femp->count) {
 229                         hint_femp->eidx = EXFAT_HINT_NONE;
 230                         return dentry;
 231                 }
 232
 233                 exfat_chain_dup(&clu, &hint_femp->cur);
 234         } else {
 235                 exfat_chain_dup(&clu, p_dir);
 236                 dentry = 0;
 237         }
 238
 239         while (clu.dir != EXFAT_EOF_CLUSTER) {
 240                 i = dentry & (dentries_per_clu - 1);
 241
 242                 for (; i < dentries_per_clu; i++, dentry++) {
 243                         ep = exfat_get_dentry(sb, &clu, i, &bh, NULL);
 244                         if (!ep)
 245                                 return -EIO;
 246                         type = exfat_get_entry_type(ep);
 247                         brelse(bh);
 248
 249                         if (type == TYPE_UNUSED || type == TYPE_DELETED) {
 250                                 num_empty++;
 251                                 if (hint_femp->eidx == EXFAT_HINT_NONE) {
 252                                         hint_femp->eidx = dentry;
 253                                         hint_femp->count = CNT_UNUSED_NOHIT;
 254                                         exfat_chain_set(&hint_femp->cur,
 255                                                 clu.dir, clu.size, clu.flags);
 256                                 }
 257
 258                                 if (type == TYPE_UNUSED &&
 259                                     hint_femp->count != CNT_UNUSED_HIT)
 260                                         hint_femp->count = CNT_UNUSED_HIT;
 261                         } else {
 262                                 if (hint_femp->eidx != EXFAT_HINT_NONE &&
 263                                     hint_femp->count == CNT_UNUSED_HIT) {
 264                                         /* unused empty group means
 265                                          * an empty group which includes
 266                                          * unused dentry
 267                                          */
 268                                         exfat_fs_error(sb,
 269                                                 "found bogus dentry(%d) beyond unused empty group(%d) (start_clu : %u, cur_clu : %u)",
 270                                                 dentry, hint_femp->eidx,
 271                                                 p_dir->dir, clu.dir);
 272                                         return -EIO;
 273                                 }
 274
 275                                 num_empty = 0;
 276                                 hint_femp->eidx = EXFAT_HINT_NONE;
 277                         }
 278
 279                         if (num_empty >= num_entries) {
 280                                 /* found and invalidate hint_femp */
 281                                 hint_femp->eidx = EXFAT_HINT_NONE;
 282                                 return (dentry - (num_entries - 1));
 283                         }
 284                 }
 285
 286                 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
 287                         if (--clu.size > 0)
 288                                 clu.dir++;
 289                         else
 290                                 clu.dir = EXFAT_EOF_CLUSTER;
 291                 } else {
 292                         if (exfat_get_next_cluster(sb, &clu.dir))
 293                                 return -EIO;
 294                 }
 295         }
 296
 297         return -ENOSPC;
 298 }
 299
 300 static int exfat_check_max_dentries(struct inode *inode)
 301 {
 302         if (EXFAT_B_TO_DEN(i_size_read(inode)) >= MAX_EXFAT_DENTRIES) {
 303                 /*
 304                  * exFAT spec allows a dir to grow upto 8388608(256MB)
 305                  * dentries
 306                  */
 307                 return -ENOSPC;
 308         }
 309         return 0;
 310 }
 311
 312 /* find empty directory entry.
 313  * if there isn't any empty slot, expand cluster chain.
 314  */
 315 static int exfat_find_empty_entry(struct inode *inode,
 316                 struct exfat_chain *p_dir, int num_entries)
 317 {
 318         int dentry;
 319         unsigned int ret, last_clu;
 320         sector_t sector;
 321         loff_t size = 0;
 322         struct exfat_chain clu;
 323         struct exfat_dentry *ep = NULL;
 324         struct super_block *sb = inode->i_sb;
 325         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 326         struct exfat_inode_info *ei = EXFAT_I(inode);
 327         struct exfat_hint_femp hint_femp;
 328
 329         hint_femp.eidx = EXFAT_HINT_NONE;
 330
 331         if (ei->hint_femp.eidx != EXFAT_HINT_NONE) {
 332                 memcpy(&hint_femp, &ei->hint_femp,
 333                                 sizeof(struct exfat_hint_femp));
 334                 ei->hint_femp.eidx = EXFAT_HINT_NONE;
 335         }
 336
 337         while ((dentry = exfat_search_empty_slot(sb, &hint_femp, p_dir,
 338                                         num_entries)) < 0) {
 339                 if (dentry == -EIO)
 340                         break;
 341
 342                 if (exfat_check_max_dentries(inode))
 343                         return -ENOSPC;
 344
 345                 /* we trust p_dir->size regardless of FAT type */
 346                 if (exfat_find_last_cluster(sb, p_dir, &last_clu))
 347                         return -EIO;
 348
 349                 /*
 350                  * Allocate new cluster to this directory
 351                  */
 352                 exfat_chain_set(&clu, last_clu + 1, 0, p_dir->flags);
 353
 354                 /* allocate a cluster */
 355                 ret = exfat_alloc_cluster(inode, 1, &clu);
 356                 if (ret)
 357                         return ret;
 358
 359                 if (exfat_zeroed_cluster(inode, clu.dir))
 360                         return -EIO;
 361
 362                 /* append to the FAT chain */
 363                 if (clu.flags != p_dir->flags) {
 364                         /* no-fat-chain bit is disabled,
 365                          * so fat-chain should be synced with alloc-bitmap
 366                          */
 367                         exfat_chain_cont_cluster(sb, p_dir->dir, p_dir->size);
 368                         p_dir->flags = ALLOC_FAT_CHAIN;
 369                         hint_femp.cur.flags = ALLOC_FAT_CHAIN;
 370                 }
 371
 372                 if (clu.flags == ALLOC_FAT_CHAIN)
 373                         if (exfat_ent_set(sb, last_clu, clu.dir))
 374                                 return -EIO;
 375
 376                 if (hint_femp.eidx == EXFAT_HINT_NONE) {
 377                         /* the special case that new dentry
 378                          * should be allocated from the start of new cluster
 379                          */
 380                         hint_femp.eidx = EXFAT_B_TO_DEN_IDX(p_dir->size, sbi);
 381                         hint_femp.count = sbi->dentries_per_clu;
 382
 383                         exfat_chain_set(&hint_femp.cur, clu.dir, 0, clu.flags);
 384                 }
 385                 hint_femp.cur.size++;
 386                 p_dir->size++;
 387                 size = EXFAT_CLU_TO_B(p_dir->size, sbi);
 388
 389                 /* update the directory entry */
 390                 if (p_dir->dir != sbi->root_dir) {
 391                         struct buffer_head *bh;
 392
 393                         ep = exfat_get_dentry(sb,
 394                                 &(ei->dir), ei->entry + 1, &bh, &sector);
 395                         if (!ep)
 396                                 return -EIO;
 397
 398                         ep->dentry.stream.valid_size = cpu_to_le64(size);
 399                         ep->dentry.stream.size = ep->dentry.stream.valid_size;
 400                         ep->dentry.stream.flags = p_dir->flags;
 401                         exfat_update_bh(sb, bh, IS_DIRSYNC(inode));
 402                         brelse(bh);
 403                         if (exfat_update_dir_chksum(inode, &(ei->dir),
 404                             ei->entry))
 405                                 return -EIO;
 406                 }
 407
 408                 /* directory inode should be updated in here */
 409                 i_size_write(inode, size);
 410                 EXFAT_I(inode)->i_size_ondisk += sbi->cluster_size;
 411                 EXFAT_I(inode)->i_size_aligned += sbi->cluster_size;
 412                 EXFAT_I(inode)->flags = p_dir->flags;
 413                 inode->i_blocks += 1 << sbi->sect_per_clus_bits;
 414         }
 415
 416         return dentry;
 417 }
 418
 419 /*
 420  * Name Resolution Functions :
 421  * Zero if it was successful; otherwise nonzero.
 422  */
 423 static int __exfat_resolve_path(struct inode *inode, const unsigned char *path,
 424                 struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname,
 425                 int lookup)
 426 {
 427         int namelen;
 428         int lossy = NLS_NAME_NO_LOSSY;
 429         struct super_block *sb = inode->i_sb;
 430         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 431         struct exfat_inode_info *ei = EXFAT_I(inode);
 432
 433         /* strip all trailing periods */
 434         namelen = exfat_striptail_len(strlen(path), path);
 435         if (!namelen)
 436                 return -ENOENT;
 437
 438         if (strlen(path) > (MAX_NAME_LENGTH * MAX_CHARSET_SIZE))
 439                 return -ENAMETOOLONG;
 440
 441         /*
 442          * strip all leading spaces :
 443          * "MS windows 7" supports leading spaces.
 444          * So we should skip this preprocessing for compatibility.
 445          */
 446
 447         /* file name conversion :
 448          * If lookup case, we allow bad-name for compatibility.
 449          */
 450         namelen = exfat_nls_to_utf16(sb, path, namelen, p_uniname,
 451                         &lossy);
 452         if (namelen < 0)
 453                 return namelen; /* return error value */
 454
 455         if ((lossy && !lookup) || !namelen)
 456                 return -EINVAL;
 457
 458         exfat_chain_set(p_dir, ei->start_clu,
 459                 EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags);
 460
 461         return 0;
 462 }
 463
 464 static inline int exfat_resolve_path(struct inode *inode,
 465                 const unsigned char *path, struct exfat_chain *dir,
 466                 struct exfat_uni_name *uni)
 467 {
 468         return __exfat_resolve_path(inode, path, dir, uni, 0);
 469 }
 470
 471 static inline int exfat_resolve_path_for_lookup(struct inode *inode,
 472                 const unsigned char *path, struct exfat_chain *dir,
 473                 struct exfat_uni_name *uni)
 474 {
 475         return __exfat_resolve_path(inode, path, dir, uni, 1);
 476 }
 477
 478 static inline loff_t exfat_make_i_pos(struct exfat_dir_entry *info)
 479 {
 480         return ((loff_t) info->dir.dir << 32) | (info->entry & 0xffffffff);
 481 }
 482
 483 static int exfat_add_entry(struct inode *inode, const char *path,
 484                 struct exfat_chain *p_dir, unsigned int type,
 485                 struct exfat_dir_entry *info)
 486 {
 487         int ret, dentry, num_entries;
 488         struct super_block *sb = inode->i_sb;
 489         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 490         struct exfat_uni_name uniname;
 491         struct exfat_chain clu;
 492         int clu_size = 0;
 493         unsigned int start_clu = EXFAT_FREE_CLUSTER;
 494
 495         ret = exfat_resolve_path(inode, path, p_dir, &uniname);
 496         if (ret)
 497                 goto out;
 498
 499         num_entries = exfat_calc_num_entries(&uniname);
 500         if (num_entries < 0) {
 501                 ret = num_entries;
 502                 goto out;
 503         }
 504
 505         /* exfat_find_empty_entry must be called before alloc_cluster() */
 506         dentry = exfat_find_empty_entry(inode, p_dir, num_entries);
 507         if (dentry < 0) {
 508                 ret = dentry; /* -EIO or -ENOSPC */
 509                 goto out;
 510         }
 511
 512         if (type == TYPE_DIR) {
 513                 ret = exfat_alloc_new_dir(inode, &clu);
 514                 if (ret)
 515                         goto out;
 516                 start_clu = clu.dir;
 517                 clu_size = sbi->cluster_size;
 518         }
 519
 520         /* update the directory entry */
 521         /* fill the dos name directory entry information of the created file.
 522          * the first cluster is not determined yet. (0)
 523          */
 524         ret = exfat_init_dir_entry(inode, p_dir, dentry, type,
 525                 start_clu, clu_size);
 526         if (ret)
 527                 goto out;
 528
 529         ret = exfat_init_ext_entry(inode, p_dir, dentry, num_entries, &uniname);
 530         if (ret)
 531                 goto out;
 532
 533         memcpy(&info->dir, p_dir, sizeof(struct exfat_chain));
 534         info->entry = dentry;
 535         info->flags = ALLOC_NO_FAT_CHAIN;
 536         info->type = type;
 537
 538         if (type == TYPE_FILE) {
 539                 info->attr = ATTR_ARCHIVE;
 540                 info->start_clu = EXFAT_EOF_CLUSTER;
 541                 info->size = 0;
 542                 info->num_subdirs = 0;
 543         } else {
 544                 int count;
 545                 struct exfat_chain cdir;
 546
 547                 info->attr = ATTR_SUBDIR;
 548                 info->start_clu = start_clu;
 549                 info->size = clu_size;
 550
 551                 exfat_chain_set(&cdir, info->start_clu,
 552                         EXFAT_B_TO_CLU(info->size, sbi), info->flags);
 553                 count = exfat_count_dir_entries(sb, &cdir);
 554                 if (count < 0)
 555                         return -EIO;
 556                 info->num_subdirs = count + EXFAT_MIN_SUBDIR;
 557         }
 558         memset(&info->crtime, 0, sizeof(info->crtime));
 559         memset(&info->mtime, 0, sizeof(info->mtime));
 560         memset(&info->atime, 0, sizeof(info->atime));
 561 out:
 562         return ret;
 563 }
 564
 565 static int exfat_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 566                 bool excl)
 567 {
 568         struct super_block *sb = dir->i_sb;
 569         struct inode *inode;
 570         struct exfat_chain cdir;
 571         struct exfat_dir_entry info;
 572         loff_t i_pos;
 573         int err;
 574
 575         mutex_lock(&EXFAT_SB(sb)->s_lock);
 576         exfat_set_vol_flags(sb, VOL_DIRTY);
 577         err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_FILE,
 578                 &info);
 579         exfat_set_vol_flags(sb, VOL_CLEAN);
 580         if (err)
 581                 goto unlock;
 582
 583         inode_inc_iversion(dir);
 584         dir->i_ctime = dir->i_mtime = current_time(dir);
 585         if (IS_DIRSYNC(dir))
 586                 exfat_sync_inode(dir);
 587         else
 588                 mark_inode_dirty(dir);
 589
 590         i_pos = exfat_make_i_pos(&info);
 591         inode = exfat_build_inode(sb, &info, i_pos);
 592         if (IS_ERR(inode))
 593                 goto unlock;
 594
 595         inode_inc_iversion(inode);
 596         inode->i_mtime = inode->i_atime = inode->i_ctime =
 597                 EXFAT_I(inode)->i_crtime = current_time(inode);
 598         exfat_truncate_atime(&inode->i_atime);
 599         /* timestamp is already written, so mark_inode_dirty() is unneeded. */
 600
 601         d_instantiate(dentry, inode);
 602 unlock:
 603         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 604         return err;
 605 }
 606
 607 /* lookup a file */
 608 static int exfat_find(struct inode *dir, struct qstr *qname,
 609                 struct exfat_dir_entry *info)
 610 {
 611         int ret, dentry, num_entries, count;
 612         struct exfat_chain cdir;
 613         struct exfat_uni_name uni_name;
 614         struct exfat_dentry *ep, *ep2;
 615         struct exfat_entry_set_cache *es = NULL;
 616         struct super_block *sb = dir->i_sb;
 617         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 618         struct exfat_inode_info *ei = EXFAT_I(dir);
 619
 620         if (qname->len == 0)
 621                 return -ENOENT;
 622
 623         /* check the validity of directory name in the given pathname */
 624         ret = exfat_resolve_path_for_lookup(dir, qname->name, &cdir, &uni_name);
 625         if (ret)
 626                 return ret;
 627
 628         num_entries = exfat_calc_num_entries(&uni_name);
 629         if (num_entries < 0)
 630                 return num_entries;
 631
 632         /* check the validation of hint_stat and initialize it if required */
 633         if (ei->version != (inode_peek_iversion_raw(dir) & 0xffffffff)) {
 634                 ei->hint_stat.clu = cdir.dir;
 635                 ei->hint_stat.eidx = 0;
 636                 ei->version = (inode_peek_iversion_raw(dir) & 0xffffffff);
 637                 ei->hint_femp.eidx = EXFAT_HINT_NONE;
 638         }
 639
 640         /* search the file name for directories */
 641         dentry = exfat_find_dir_entry(sb, ei, &cdir, &uni_name,
 642                         num_entries, TYPE_ALL);
 643
 644         if ((dentry < 0) && (dentry != -EEXIST))
 645                 return dentry; /* -error value */
 646
 647         memcpy(&info->dir, &cdir.dir, sizeof(struct exfat_chain));
 648         info->entry = dentry;
 649         info->num_subdirs = 0;
 650
 651         /* root directory itself */
 652         if (unlikely(dentry == -EEXIST)) {
 653                 int num_clu = 0;
 654
 655                 info->type = TYPE_DIR;
 656                 info->attr = ATTR_SUBDIR;
 657                 info->flags = ALLOC_FAT_CHAIN;
 658                 info->start_clu = sbi->root_dir;
 659                 memset(&info->crtime, 0, sizeof(info->crtime));
 660                 memset(&info->mtime, 0, sizeof(info->mtime));
 661                 memset(&info->atime, 0, sizeof(info->atime));
 662
 663                 exfat_chain_set(&cdir, sbi->root_dir, 0, ALLOC_FAT_CHAIN);
 664                 if (exfat_count_num_clusters(sb, &cdir, &num_clu))
 665                         return -EIO;
 666                 info->size = num_clu << sbi->cluster_size_bits;
 667
 668                 count = exfat_count_dir_entries(sb, &cdir);
 669                 if (count < 0)
 670                         return -EIO;
 671
 672                 info->num_subdirs = count;
 673         } else {
 674                 es = exfat_get_dentry_set(sb, &cdir, dentry, ES_2_ENTRIES, &ep);
 675                 if (!es)
 676                         return -EIO;
 677                 ep2 = ep + 1;
 678
 679                 info->type = exfat_get_entry_type(ep);
 680                 info->attr = le16_to_cpu(ep->dentry.file.attr);
 681                 info->size = le64_to_cpu(ep2->dentry.stream.valid_size);
 682                 if ((info->type == TYPE_FILE) && (info->size == 0)) {
 683                         info->flags = ALLOC_NO_FAT_CHAIN;
 684                         info->start_clu = EXFAT_EOF_CLUSTER;
 685                 } else {
 686                         info->flags = ep2->dentry.stream.flags;
 687                         info->start_clu =
 688                                 le32_to_cpu(ep2->dentry.stream.start_clu);
 689                 }
 690
 691                 if (ei->start_clu == EXFAT_FREE_CLUSTER) {
 692                         exfat_fs_error(sb,
 693                                 "non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)",
 694                                 i_size_read(dir), ei->dir.dir, ei->entry);
 695                         return -EIO;
 696                 }
 697
 698                 exfat_get_entry_time(sbi, &info->crtime,
 699                                 ep->dentry.file.create_tz,
 700                                 ep->dentry.file.create_time,
 701                                 ep->dentry.file.create_date,
 702                                 ep->dentry.file.create_time_ms);
 703                 exfat_get_entry_time(sbi, &info->mtime,
 704                                 ep->dentry.file.modify_tz,
 705                                 ep->dentry.file.modify_time,
 706                                 ep->dentry.file.modify_date,
 707                                 ep->dentry.file.modify_time_ms);
 708                 exfat_get_entry_time(sbi, &info->atime,
 709                                 ep->dentry.file.access_tz,
 710                                 ep->dentry.file.access_time,
 711                                 ep->dentry.file.access_date,
 712                                 0);
 713                 kfree(es);
 714
 715                 if (info->type == TYPE_DIR) {
 716                         exfat_chain_set(&cdir, info->start_clu,
 717                                 EXFAT_B_TO_CLU(info->size, sbi), info->flags);
 718                         count = exfat_count_dir_entries(sb, &cdir);
 719                         if (count < 0)
 720                                 return -EIO;
 721
 722                         info->num_subdirs = count + EXFAT_MIN_SUBDIR;
 723                 }
 724         }
 725         return 0;
 726 }
 727
 728 static int exfat_d_anon_disconn(struct dentry *dentry)
 729 {
 730         return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED);
 731 }
 732
 733 static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry,
 734                 unsigned int flags)
 735 {
 736         struct super_block *sb = dir->i_sb;
 737         struct inode *inode;
 738         struct dentry *alias;
 739         struct exfat_dir_entry info;
 740         int err;
 741         loff_t i_pos;
 742         mode_t i_mode;
 743
 744         mutex_lock(&EXFAT_SB(sb)->s_lock);
 745         err = exfat_find(dir, &dentry->d_name, &info);
 746         if (err) {
 747                 if (err == -ENOENT) {
 748                         inode = NULL;
 749                         goto out;
 750                 }
 751                 goto unlock;
 752         }
 753
 754         i_pos = exfat_make_i_pos(&info);
 755         inode = exfat_build_inode(sb, &info, i_pos);
 756         if (IS_ERR(inode)) {
 757                 err = PTR_ERR(inode);
 758                 goto unlock;
 759         }
 760
 761         i_mode = inode->i_mode;
 762         alias = d_find_alias(inode);
 763
 764         /*
 765          * Checking "alias->d_parent == dentry->d_parent" to make sure
 766          * FS is not corrupted (especially double linked dir).
 767          */
 768         if (alias && alias->d_parent == dentry->d_parent &&
 769                         !exfat_d_anon_disconn(alias)) {
 770
 771                 /*
 772                  * Unhashed alias is able to exist because of revalidate()
 773                  * called by lookup_fast. You can easily make this status
 774                  * by calling create and lookup concurrently
 775                  * In such case, we reuse an alias instead of new dentry
 776                  */
 777                 if (d_unhashed(alias)) {
 778                         WARN_ON(alias->d_name.hash_len !=
 779                                 dentry->d_name.hash_len);
 780                         exfat_msg(sb, KERN_INFO,
 781                                 "rehashed a dentry(%p) in read lookup", alias);
 782                         d_drop(dentry);
 783                         d_rehash(alias);
 784                 } else if (!S_ISDIR(i_mode)) {
 785                         /*
 786                          * This inode has non anonymous-DCACHE_DISCONNECTED
 787                          * dentry. This means, the user did ->lookup() by an
 788                          * another name (longname vs 8.3 alias of it) in past.
 789                          *
 790                          * Switch to new one for reason of locality if possible.
 791                          */
 792                         d_move(alias, dentry);
 793                 }
 794                 iput(inode);
 795                 mutex_unlock(&EXFAT_SB(sb)->s_lock);
 796                 return alias;
 797         }
 798         dput(alias);
 799 out:
 800         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 801         if (!inode)
 802                 exfat_d_version_set(dentry, inode_query_iversion(dir));
 803
 804         return d_splice_alias(inode, dentry);
 805 unlock:
 806         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 807         return ERR_PTR(err);
 808 }
 809
 810 /* remove an entry, BUT don't truncate */
 811 static int exfat_unlink(struct inode *dir, struct dentry *dentry)
 812 {
 813         struct exfat_chain cdir;
 814         struct exfat_dentry *ep;
 815         struct super_block *sb = dir->i_sb;
 816         struct inode *inode = dentry->d_inode;
 817         struct exfat_inode_info *ei = EXFAT_I(inode);
 818         struct buffer_head *bh;
 819         sector_t sector;
 820         int num_entries, entry, err = 0;
 821
 822         mutex_lock(&EXFAT_SB(sb)->s_lock);
 823         exfat_chain_dup(&cdir, &ei->dir);
 824         entry = ei->entry;
 825         if (ei->dir.dir == DIR_DELETED) {
 826                 exfat_msg(sb, KERN_ERR, "abnormal access to deleted dentry");
 827                 err = -ENOENT;
 828                 goto unlock;
 829         }
 830
 831         ep = exfat_get_dentry(sb, &cdir, entry, &bh, &sector);
 832         if (!ep) {
 833                 err = -EIO;
 834                 goto unlock;
 835         }
 836         num_entries = exfat_count_ext_entries(sb, &cdir, entry, ep);
 837         if (num_entries < 0) {
 838                 err = -EIO;
 839                 brelse(bh);
 840                 goto unlock;
 841         }
 842         num_entries++;
 843         brelse(bh);
 844
 845         exfat_set_vol_flags(sb, VOL_DIRTY);
 846         /* update the directory entry */
 847         if (exfat_remove_entries(dir, &cdir, entry, 0, num_entries)) {
 848                 err = -EIO;
 849                 goto unlock;
 850         }
 851
 852         /* This doesn't modify ei */
 853         ei->dir.dir = DIR_DELETED;
 854         exfat_set_vol_flags(sb, VOL_CLEAN);
 855
 856         inode_inc_iversion(dir);
 857         dir->i_mtime = dir->i_atime = current_time(dir);
 858         exfat_truncate_atime(&dir->i_atime);
 859         if (IS_DIRSYNC(dir))
 860                 exfat_sync_inode(dir);
 861         else
 862                 mark_inode_dirty(dir);
 863
 864         clear_nlink(inode);
 865         inode->i_mtime = inode->i_atime = current_time(inode);
 866         exfat_truncate_atime(&inode->i_atime);
 867         exfat_unhash_inode(inode);
 868         exfat_d_version_set(dentry, inode_query_iversion(dir));
 869 unlock:
 870         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 871         return err;
 872 }
 873
 874 static int exfat_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 875 {
 876         struct super_block *sb = dir->i_sb;
 877         struct inode *inode;
 878         struct exfat_dir_entry info;
 879         struct exfat_chain cdir;
 880         loff_t i_pos;
 881         int err;
 882
 883         mutex_lock(&EXFAT_SB(sb)->s_lock);
 884         exfat_set_vol_flags(sb, VOL_DIRTY);
 885         err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_DIR,
 886                 &info);
 887         exfat_set_vol_flags(sb, VOL_CLEAN);
 888         if (err)
 889                 goto unlock;
 890
 891         inode_inc_iversion(dir);
 892         dir->i_ctime = dir->i_mtime = current_time(dir);
 893         if (IS_DIRSYNC(dir))
 894                 exfat_sync_inode(dir);
 895         else
 896                 mark_inode_dirty(dir);
 897         inc_nlink(dir);
 898
 899         i_pos = exfat_make_i_pos(&info);
 900         inode = exfat_build_inode(sb, &info, i_pos);
 901         if (IS_ERR(inode)) {
 902                 err = PTR_ERR(inode);
 903                 goto unlock;
 904         }
 905
 906         inode_inc_iversion(inode);
 907         inode->i_mtime = inode->i_atime = inode->i_ctime =
 908                 EXFAT_I(inode)->i_crtime = current_time(inode);
 909         exfat_truncate_atime(&inode->i_atime);
 910         /* timestamp is already written, so mark_inode_dirty() is unneeded. */
 911
 912         d_instantiate(dentry, inode);
 913
 914 unlock:
 915         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 916         return err;
 917 }
 918
 919 static int exfat_check_dir_empty(struct super_block *sb,
 920                 struct exfat_chain *p_dir)
 921 {
 922         int i, dentries_per_clu;
 923         unsigned int type;
 924         struct exfat_chain clu;
 925         struct exfat_dentry *ep;
 926         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 927         struct buffer_head *bh;
 928
 929         dentries_per_clu = sbi->dentries_per_clu;
 930
 931         exfat_chain_dup(&clu, p_dir);
 932
 933         while (clu.dir != EXFAT_EOF_CLUSTER) {
 934                 for (i = 0; i < dentries_per_clu; i++) {
 935                         ep = exfat_get_dentry(sb, &clu, i, &bh, NULL);
 936                         if (!ep)
 937                                 return -EIO;
 938                         type = exfat_get_entry_type(ep);
 939                         brelse(bh);
 940                         if (type == TYPE_UNUSED)
 941                                 return 0;
 942
 943                         if (type != TYPE_FILE && type != TYPE_DIR)
 944                                 continue;
 945
 946                         return -ENOTEMPTY;
 947                 }
 948
 949                 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
 950                         if (--clu.size > 0)
 951                                 clu.dir++;
 952                         else
 953                                 clu.dir = EXFAT_EOF_CLUSTER;
 954                 } else {
 955                         if (exfat_get_next_cluster(sb, &(clu.dir)))
 956                                 return -EIO;
 957                 }
 958         }
 959
 960         return 0;
 961 }
 962
 963 static int exfat_rmdir(struct inode *dir, struct dentry *dentry)
 964 {
 965         struct inode *inode = dentry->d_inode;
 966         struct exfat_dentry *ep;
 967         struct exfat_chain cdir, clu_to_free;
 968         struct super_block *sb = inode->i_sb;
 969         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 970         struct exfat_inode_info *ei = EXFAT_I(inode);
 971         struct buffer_head *bh;
 972         sector_t sector;
 973         int num_entries, entry, err;
 974
 975         mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
 976
 977         exfat_chain_dup(&cdir, &ei->dir);
 978         entry = ei->entry;
 979
 980         if (ei->dir.dir == DIR_DELETED) {
 981                 exfat_msg(sb, KERN_ERR, "abnormal access to deleted dentry");
 982                 err = -ENOENT;
 983                 goto unlock;
 984         }
 985
 986         exfat_set_vol_flags(sb, VOL_DIRTY);
 987         exfat_chain_set(&clu_to_free, ei->start_clu,
 988                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi), ei->flags);
 989
 990         err = exfat_check_dir_empty(sb, &clu_to_free);
 991         if (err) {
 992                 if (err == -EIO)
 993                         exfat_msg(sb, KERN_ERR,
 994                                 "failed to exfat_check_dir_empty : err(%d)",
 995                                 err);
 996                 goto unlock;
 997         }
 998
 999         ep = exfat_get_dentry(sb, &cdir, entry, &bh, &sector);
1000         if (!ep) {
1001                 err = -EIO;
1002                 goto unlock;
1003         }
1004
1005         num_entries = exfat_count_ext_entries(sb, &cdir, entry, ep);
1006         if (num_entries < 0) {
1007                 err = -EIO;
1008                 brelse(bh);
1009                 goto unlock;
1010         }
1011         num_entries++;
1012         brelse(bh);
1013
1014         err = exfat_remove_entries(dir, &cdir, entry, 0, num_entries);
1015         if (err) {
1016                 exfat_msg(sb, KERN_ERR,
1017                                 "failed to exfat_remove_entries : err(%d)",
1018                                 err);
1019                 goto unlock;
1020         }
1021         ei->dir.dir = DIR_DELETED;
1022         exfat_set_vol_flags(sb, VOL_CLEAN);
1023
1024         inode_inc_iversion(dir);
1025         dir->i_mtime = dir->i_atime = current_time(dir);
1026         exfat_truncate_atime(&dir->i_atime);
1027         if (IS_DIRSYNC(dir))
1028                 exfat_sync_inode(dir);
1029         else
1030                 mark_inode_dirty(dir);
1031         drop_nlink(dir);
1032
1033         clear_nlink(inode);
1034         inode->i_mtime = inode->i_atime = current_time(inode);
1035         exfat_truncate_atime(&inode->i_atime);
1036         exfat_unhash_inode(inode);
1037         exfat_d_version_set(dentry, inode_query_iversion(dir));
1038 unlock:
1039         mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
1040         return err;
1041 }
1042
1043 static int exfat_rename_file(struct inode *inode, struct exfat_chain *p_dir,
1044                 int oldentry, struct exfat_uni_name *p_uniname,
1045                 struct exfat_inode_info *ei)
1046 {
1047         int ret, num_old_entries, num_new_entries;
1048         sector_t sector_old, sector_new;
1049         struct exfat_dentry *epold, *epnew;
1050         struct super_block *sb = inode->i_sb;
1051         struct buffer_head *new_bh, *old_bh;
1052         int sync = IS_DIRSYNC(inode);
1053
1054         epold = exfat_get_dentry(sb, p_dir, oldentry, &old_bh, &sector_old);
1055         if (!epold)
1056                 return -EIO;
1057
1058         num_old_entries = exfat_count_ext_entries(sb, p_dir, oldentry, epold);
1059         if (num_old_entries < 0)
1060                 return -EIO;
1061         num_old_entries++;
1062
1063         num_new_entries = exfat_calc_num_entries(p_uniname);
1064         if (num_new_entries < 0)
1065                 return num_new_entries;
1066
1067         if (num_old_entries < num_new_entries) {
1068                 int newentry;
1069
1070                 newentry =
1071                         exfat_find_empty_entry(inode, p_dir, num_new_entries);
1072                 if (newentry < 0)
1073                         return newentry; /* -EIO or -ENOSPC */
1074
1075                 epnew = exfat_get_dentry(sb, p_dir, newentry, &new_bh,
1076                         &sector_new);
1077                 if (!epnew)
1078                         return -EIO;
1079
1080                 memcpy(epnew, epold, DENTRY_SIZE);
1081                 if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1082                         epnew->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1083                         ei->attr |= ATTR_ARCHIVE;
1084                 }
1085                 exfat_update_bh(sb, new_bh, sync);
1086                 brelse(old_bh);
1087                 brelse(new_bh);
1088
1089                 epold = exfat_get_dentry(sb, p_dir, oldentry + 1, &old_bh,
1090                         &sector_old);
1091                 epnew = exfat_get_dentry(sb, p_dir, newentry + 1, &new_bh,
1092                         &sector_new);
1093                 if (!epold || !epnew)
1094                         return -EIO;
1095
1096                 memcpy(epnew, epold, DENTRY_SIZE);
1097                 exfat_update_bh(sb, new_bh, sync);
1098                 brelse(old_bh);
1099                 brelse(new_bh);
1100
1101                 ret = exfat_init_ext_entry(inode, p_dir, newentry,
1102                         num_new_entries, p_uniname);
1103                 if (ret)
1104                         return ret;
1105
1106                 exfat_remove_entries(inode, p_dir, oldentry, 0,
1107                         num_old_entries);
1108                 ei->entry = newentry;
1109         } else {
1110                 if (exfat_get_entry_type(epold) == TYPE_FILE) {
1111                         epold->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1112                         ei->attr |= ATTR_ARCHIVE;
1113                 }
1114                 exfat_update_bh(sb, old_bh, sync);
1115                 brelse(old_bh);
1116                 ret = exfat_init_ext_entry(inode, p_dir, oldentry,
1117                         num_new_entries, p_uniname);
1118                 if (ret)
1119                         return ret;
1120
1121                 exfat_remove_entries(inode, p_dir, oldentry, num_new_entries,
1122                         num_old_entries);
1123         }
1124         return 0;
1125 }
1126
1127 static int exfat_move_file(struct inode *inode, struct exfat_chain *p_olddir,
1128                 int oldentry, struct exfat_chain *p_newdir,
1129                 struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei)
1130 {
1131         int ret, newentry, num_new_entries, num_old_entries;
1132         sector_t sector_mov, sector_new;
1133         struct exfat_dentry *epmov, *epnew;
1134         struct super_block *sb = inode->i_sb;
1135         struct buffer_head *mov_bh, *new_bh;
1136
1137         epmov = exfat_get_dentry(sb, p_olddir, oldentry, &mov_bh, &sector_mov);
1138         if (!epmov)
1139                 return -EIO;
1140
1141         /* check if the source and target directory is the same */
1142         if (exfat_get_entry_type(epmov) == TYPE_DIR &&
1143             le32_to_cpu(epmov->dentry.stream.start_clu) == p_newdir->dir)
1144                 return -EINVAL;
1145
1146         num_old_entries = exfat_count_ext_entries(sb, p_olddir, oldentry,
1147                 epmov);
1148         if (num_old_entries < 0)
1149                 return -EIO;
1150         num_old_entries++;
1151
1152         num_new_entries = exfat_calc_num_entries(p_uniname);
1153         if (num_new_entries < 0)
1154                 return num_new_entries;
1155
1156         newentry = exfat_find_empty_entry(inode, p_newdir, num_new_entries);
1157         if (newentry < 0)
1158                 return newentry; /* -EIO or -ENOSPC */
1159
1160         epnew = exfat_get_dentry(sb, p_newdir, newentry, &new_bh, &sector_new);
1161         if (!epnew)
1162                 return -EIO;
1163
1164         memcpy(epnew, epmov, DENTRY_SIZE);
1165         if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1166                 epnew->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1167                 ei->attr |= ATTR_ARCHIVE;
1168         }
1169         exfat_update_bh(sb, new_bh, IS_DIRSYNC(inode));
1170         brelse(mov_bh);
1171         brelse(new_bh);
1172
1173         epmov = exfat_get_dentry(sb, p_olddir, oldentry + 1, &mov_bh,
1174                 &sector_mov);
1175         epnew = exfat_get_dentry(sb, p_newdir, newentry + 1, &new_bh,
1176                 &sector_new);
1177         if (!epmov || !epnew)
1178                 return -EIO;
1179
1180         memcpy(epnew, epmov, DENTRY_SIZE);
1181         exfat_update_bh(sb, new_bh, IS_DIRSYNC(inode));
1182         brelse(mov_bh);
1183         brelse(new_bh);
1184
1185         ret = exfat_init_ext_entry(inode, p_newdir, newentry, num_new_entries,
1186                 p_uniname);
1187         if (ret)
1188                 return ret;
1189
1190         exfat_remove_entries(inode, p_olddir, oldentry, 0, num_old_entries);
1191
1192         exfat_chain_set(&ei->dir, p_newdir->dir, p_newdir->size,
1193                 p_newdir->flags);
1194
1195         ei->entry = newentry;
1196         return 0;
1197 }
1198
1199 static void exfat_update_parent_info(struct exfat_inode_info *ei,
1200                 struct inode *parent_inode)
1201 {
1202         struct exfat_sb_info *sbi = EXFAT_SB(parent_inode->i_sb);
1203         struct exfat_inode_info *parent_ei = EXFAT_I(parent_inode);
1204         loff_t parent_isize = i_size_read(parent_inode);
1205
1206         /*
1207          * the problem that struct exfat_inode_info caches wrong parent info.
1208          *
1209          * because of flag-mismatch of ei->dir,
1210          * there is abnormal traversing cluster chain.
1211          */
1212         if (unlikely(parent_ei->flags != ei->dir.flags ||
1213                      parent_isize != EXFAT_CLU_TO_B(ei->dir.size, sbi) ||
1214                      parent_ei->start_clu != ei->dir.dir)) {
1215                 exfat_chain_set(&ei->dir, parent_ei->start_clu,
1216                         EXFAT_B_TO_CLU_ROUND_UP(parent_isize, sbi),
1217                         parent_ei->flags);
1218         }
1219 }
1220
1221 /* rename or move a old file into a new file */
1222 static int __exfat_rename(struct inode *old_parent_inode,
1223                 struct exfat_inode_info *ei, struct inode *new_parent_inode,
1224                 struct dentry *new_dentry)
1225 {
1226         int ret;
1227         int dentry;
1228         struct exfat_chain olddir, newdir;
1229         struct exfat_chain *p_dir = NULL;
1230         struct exfat_uni_name uni_name;
1231         struct exfat_dentry *ep;
1232         struct super_block *sb = old_parent_inode->i_sb;
1233         struct exfat_sb_info *sbi = EXFAT_SB(sb);
1234         const unsigned char *new_path = new_dentry->d_name.name;
1235         struct inode *new_inode = new_dentry->d_inode;
1236         int num_entries;
1237         struct exfat_inode_info *new_ei = NULL;
1238         unsigned int new_entry_type = TYPE_UNUSED;
1239         int new_entry = 0;
1240         struct buffer_head *old_bh, *new_bh = NULL;
1241
1242         /* check the validity of pointer parameters */
1243         if (new_path == NULL || strlen(new_path) == 0)
1244                 return -EINVAL;
1245
1246         if (ei->dir.dir == DIR_DELETED) {
1247                 exfat_msg(sb, KERN_ERR,
1248                                 "abnormal access to deleted source dentry");
1249                 return -ENOENT;
1250         }
1251
1252         exfat_update_parent_info(ei, old_parent_inode);
1253
1254         exfat_chain_dup(&olddir, &ei->dir);
1255         dentry = ei->entry;
1256
1257         ep = exfat_get_dentry(sb, &olddir, dentry, &old_bh, NULL);
1258         if (!ep) {
1259                 ret = -EIO;
1260                 goto out;
1261         }
1262         brelse(old_bh);
1263
1264         /* check whether new dir is existing directory and empty */
1265         if (new_inode) {
1266                 ret = -EIO;
1267                 new_ei = EXFAT_I(new_inode);
1268
1269                 if (new_ei->dir.dir == DIR_DELETED) {
1270                         exfat_msg(sb, KERN_ERR,
1271                                 "abnormal access to deleted target dentry");
1272                         goto out;
1273                 }
1274
1275                 exfat_update_parent_info(new_ei, new_parent_inode);
1276
1277                 p_dir = &(new_ei->dir);
1278                 new_entry = new_ei->entry;
1279                 ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh, NULL);
1280                 if (!ep)
1281                         goto out;
1282
1283                 new_entry_type = exfat_get_entry_type(ep);
1284                 brelse(new_bh);
1285
1286                 /* if new_inode exists, update ei */
1287                 if (new_entry_type == TYPE_DIR) {
1288                         struct exfat_chain new_clu;
1289
1290                         new_clu.dir = new_ei->start_clu;
1291                         new_clu.size =
1292                                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1293                                 sbi);
1294                         new_clu.flags = new_ei->flags;
1295
1296                         ret = exfat_check_dir_empty(sb, &new_clu);
1297                         if (ret)
1298                                 goto out;
1299                 }
1300         }
1301
1302         /* check the validity of directory name in the given new pathname */
1303         ret = exfat_resolve_path(new_parent_inode, new_path, &newdir,
1304                         &uni_name);
1305         if (ret)
1306                 goto out;
1307
1308         exfat_set_vol_flags(sb, VOL_DIRTY);
1309
1310         if (olddir.dir == newdir.dir)
1311                 ret = exfat_rename_file(new_parent_inode, &olddir, dentry,
1312                                 &uni_name, ei);
1313         else
1314                 ret = exfat_move_file(new_parent_inode, &olddir, dentry,
1315                                 &newdir, &uni_name, ei);
1316
1317         if (!ret && new_inode) {
1318                 /* delete entries of new_dir */
1319                 ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh, NULL);
1320                 if (!ep) {
1321                         ret = -EIO;
1322                         goto del_out;
1323                 }
1324
1325                 num_entries = exfat_count_ext_entries(sb, p_dir, new_entry, ep);
1326                 if (num_entries < 0) {
1327                         ret = -EIO;
1328                         goto del_out;
1329                 }
1330                 brelse(new_bh);
1331
1332                 if (exfat_remove_entries(new_inode, p_dir, new_entry, 0,
1333                                 num_entries + 1)) {
1334                         ret = -EIO;
1335                         goto del_out;
1336                 }
1337
1338                 /* Free the clusters if new_inode is a dir(as if exfat_rmdir) */
1339                 if (new_entry_type == TYPE_DIR) {
1340                         /* new_ei, new_clu_to_free */
1341                         struct exfat_chain new_clu_to_free;
1342
1343                         exfat_chain_set(&new_clu_to_free, new_ei->start_clu,
1344                                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1345                                 sbi), new_ei->flags);
1346
1347                         if (exfat_free_cluster(new_inode, &new_clu_to_free)) {
1348                                 /* just set I/O error only */
1349                                 ret = -EIO;
1350                         }
1351
1352                         i_size_write(new_inode, 0);
1353                         new_ei->start_clu = EXFAT_EOF_CLUSTER;
1354                         new_ei->flags = ALLOC_NO_FAT_CHAIN;
1355                 }
1356 del_out:
1357                 /* Update new_inode ei
1358                  * Prevent syncing removed new_inode
1359                  * (new_ei is already initialized above code ("if (new_inode)")
1360                  */
1361                 new_ei->dir.dir = DIR_DELETED;
1362         }
1363         exfat_set_vol_flags(sb, VOL_CLEAN);
1364 out:
1365         return ret;
1366 }
1367
1368 static int exfat_rename(struct inode *old_dir, struct dentry *old_dentry,
1369                 struct inode *new_dir, struct dentry *new_dentry,
1370                 unsigned int flags)
1371 {
1372         struct inode *old_inode, *new_inode;
1373         struct super_block *sb = old_dir->i_sb;
1374         loff_t i_pos;
1375         int err;
1376
1377         /*
1378          * The VFS already checks for existence, so for local filesystems
1379          * the RENAME_NOREPLACE implementation is equivalent to plain rename.
1380          * Don't support any other flags
1381          */
1382         if (flags & ~RENAME_NOREPLACE)
1383                 return -EINVAL;
1384
1385         mutex_lock(&EXFAT_SB(sb)->s_lock);
1386         old_inode = old_dentry->d_inode;
1387         new_inode = new_dentry->d_inode;
1388
1389         err = __exfat_rename(old_dir, EXFAT_I(old_inode), new_dir, new_dentry);
1390         if (err)
1391                 goto unlock;
1392
1393         inode_inc_iversion(new_dir);
1394         new_dir->i_ctime = new_dir->i_mtime = new_dir->i_atime =
1395                 EXFAT_I(new_dir)->i_crtime = current_time(new_dir);
1396         exfat_truncate_atime(&new_dir->i_atime);
1397         if (IS_DIRSYNC(new_dir))
1398                 exfat_sync_inode(new_dir);
1399         else
1400                 mark_inode_dirty(new_dir);
1401
1402         i_pos = ((loff_t)EXFAT_I(old_inode)->dir.dir << 32) |
1403                 (EXFAT_I(old_inode)->entry & 0xffffffff);
1404         exfat_unhash_inode(old_inode);
1405         exfat_hash_inode(old_inode, i_pos);
1406         if (IS_DIRSYNC(new_dir))
1407                 exfat_sync_inode(old_inode);
1408         else
1409                 mark_inode_dirty(old_inode);
1410
1411         if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) {
1412                 drop_nlink(old_dir);
1413                 if (!new_inode)
1414                         inc_nlink(new_dir);
1415         }
1416
1417         inode_inc_iversion(old_dir);
1418         old_dir->i_ctime = old_dir->i_mtime = current_time(old_dir);
1419         if (IS_DIRSYNC(old_dir))
1420                 exfat_sync_inode(old_dir);
1421         else
1422                 mark_inode_dirty(old_dir);
1423
1424         if (new_inode) {
1425                 exfat_unhash_inode(new_inode);
1426
1427                 /* skip drop_nlink if new_inode already has been dropped */
1428                 if (new_inode->i_nlink) {
1429                         drop_nlink(new_inode);
1430                         if (S_ISDIR(new_inode->i_mode))
1431                                 drop_nlink(new_inode);
1432                 } else {
1433                         exfat_msg(sb, KERN_WARNING,
1434                                         "abnormal access to an inode dropped");
1435                         WARN_ON(new_inode->i_nlink == 0);
1436                 }
1437                 new_inode->i_ctime = EXFAT_I(new_inode)->i_crtime =
1438                         current_time(new_inode);
1439         }
1440
1441 unlock:
1442         mutex_unlock(&EXFAT_SB(sb)->s_lock);
1443         return err;
1444 }
1445
1446 const struct inode_operations exfat_dir_inode_operations = {
1447         .create         = exfat_create,
1448         .lookup         = exfat_lookup,
1449         .unlink         = exfat_unlink,
1450         .mkdir          = exfat_mkdir,
1451         .rmdir          = exfat_rmdir,
1452         .rename         = exfat_rename,
1453         .setattr        = exfat_setattr,
1454         .getattr        = exfat_getattr,
1455 };